In this study, a simple and fast electrochemical method was employed to synthesis molybdenum diselenide thin film. The morphology, structure and chemical composition of the nanocomposites were investigated by field emission scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The progressive effects of transition metal ions including Ni, Cu, and Co were surveyed on the hydrogen evolution activity of MoSe2 thin films. Co/MoSe2 nanocomposite thin films has significant electrocatalytic activity as compared to other samples, In order to achieve higher performance, preparing Co/MoSe2/RGO nanocomposite thin film, two strategies including layer by layer electrodeposition and co-electrodeposition has been employed. The presence of reduced graphene oxide leading to the onset potential shifts to more positive values and increase the current density. Also, results showed that the Co/MoSe2/RGO nanocomposite prepared by co-electrodeposition exhibits the best electrochemical hydrogen evolution at onset potential of -0.18 with an overpotential of -0.45 V. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.